1. Technical Field
The present invention relates to a rotary input apparatus.
2. Description of the Related Art
In general, a mobile terminal has the numbers 0-9 and the symbols * and # on a keypad of 12 keys. In addition to the numbers, there are also alphabet letters as well as consonants and vowels of Korean letters marked on such a keypad, to enable the input of information including numbers and letters. Recently, there are also navigation keys formed above the keypad equipped with a variety of functions such as phone number search, writing and managing text messages, and connecting to the Internet, etc. There are various forms of navigation keys, such as button types and rotary types, etc., but the use of rotary input apparatus is currently increasing, as they enable various functions such as menu browsing, etc.
Rotary input apparatus are used in televisions, camcorders, and PDA's (personal digital assistants), etc., as input apparatus in the form of rotary switches, rotary encoders, and rotary volume dials, etc.
In a conventional rotary input apparatus, several switches are formed on a base, and a rotational body having a center switch inserted in its center is inserted in and secured to the base. The center switch has a pressing protrusion and the rotational body has a plurality of protrusions, and the pressing protrusion and protrusions touch switches, whereby the center switch and rotational body are supported with a gap from the base.
Therefore, in such a rotary input apparatus using pressing protrusions and protrusions, the center switch and rotational body are supported entirely by the push resistance strength of the switches, so that not only is the structure weak, but also there are problems of malfunctioning due to the switches being activated even with a slight impact. Also, since the center switch is inserted in the rotational body in the conventional rotary input apparatus described above, the center switch is rotated in accordance with the rotation of the rotational body, so that if there is a text or a logo, etc., marked on the surface of the center switch, the orientation of the text or logo is changed, causing a reduction in the overall aesthetic value.
Further, another conventional rotary input apparatus is equipped with a rotating key, composed of an upper case and a lower case, and a securing button inserted in the center of the rotating key. On the reverse side of the securing button is formed a support portion, where this support portion supports the securing button while in contact with a second dome switch. Also, there is a base plate having three support portions protruding upwards, supporting the rotating key while pressing this support portion and a first dome switch attached to the reverse side of the rotating key.
However, in a rotary input apparatus comprised as above, the rotating key and securing button are supported by the push resistance strength of the first dome switch or second dome switch, respectively, so that not only is the structure unstable, but also its joining structure is weak, whereby there are problems of malfunctioning due to switches being activated even with a slight impact. In addition, since the securing button is inserted and secured in a mounting hole while being caught on a first engaging ledge of the upper case, in the conventional rotary input apparatus described above, the securing button is rotated simultaneously with the rotation of the rotating key. Therefore, if there is a text or a logo, etc., marked on the surface of the securing button, the orientation of the text or logo is changed, causing a reduction in the overall aesthetic value.
Also, a conventional rotary input apparatus is not equipped with a light emitting device, so that not only is it inconvenient to use at night, but also it is lacking in aesthetic value.